arch/arm64/crypto/sha2-ce-glue.c

   1 /*
   2  * sha2-ce-glue.c - SHA-224/SHA-256 using ARMv8 Crypto Extensions
   3  *
   4  * Copyright (C) 2014 Linaro Ltd <ard.biesheuvel@linaro.org>
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License version 2 as
   8  * published by the Free Software Foundation.
   9  */
  10
  11 #include <asm/neon.h>
  12 #include <asm/unaligned.h>
  13 #include <crypto/internal/hash.h>
  14 #include <crypto/sha.h>
  15 #include <crypto/sha256_base.h>
  16 #include <linux/cpufeature.h>
  17 #include <linux/crypto.h>
  18 #include <linux/module.h>
  19
  20 #define ASM_EXPORT(sym, val) \
  21         asm(".globl " #sym "; .set " #sym ", %0" :: "I"(val));
  22
  23 MODULE_DESCRIPTION("SHA-224/SHA-256 secure hash using ARMv8 Crypto Extensions");
  24 MODULE_AUTHOR("Ard Biesheuvel <ard.biesheuvel@linaro.org>");
  25 MODULE_LICENSE("GPL v2");
  26
  27 struct sha256_ce_state {
  28         struct sha256_state     sst;
  29         u32                     finalize;
  30 };
  31
  32 asmlinkage void sha2_ce_transform(struct sha256_ce_state *sst, u8 const *src,
  33                                   int blocks);
  34
  35 static int sha256_ce_update(struct shash_desc *desc, const u8 *data,
  36                             unsigned int len)
  37 {
  38         struct sha256_ce_state *sctx = shash_desc_ctx(desc);
  39
  40         sctx->finalize = 0;
  41         kernel_neon_begin_partial(28);
  42         sha256_base_do_update(desc, data, len,
  43                               (sha256_block_fn *)sha2_ce_transform);
  44         kernel_neon_end();
  45
  46         return 0;
  47 }
  48
  49 static int sha256_ce_finup(struct shash_desc *desc, const u8 *data,
  50                            unsigned int len, u8 *out)
  51 {
  52         struct sha256_ce_state *sctx = shash_desc_ctx(desc);
  53         bool finalize = !sctx->sst.count && !(len % SHA256_BLOCK_SIZE);
  54
  55         ASM_EXPORT(sha256_ce_offsetof_count,
  56                    offsetof(struct sha256_ce_state, sst.count));
  57         ASM_EXPORT(sha256_ce_offsetof_finalize,
  58                    offsetof(struct sha256_ce_state, finalize));
  59
  60         /*
  61          * Allow the asm code to perform the finalization if there is no
  62          * partial data and the input is a round multiple of the block size.
  63          */
  64         sctx->finalize = finalize;
  65
  66         kernel_neon_begin_partial(28);
  67         sha256_base_do_update(desc, data, len,
  68                               (sha256_block_fn *)sha2_ce_transform);
  69         if (!finalize)
  70                 sha256_base_do_finalize(desc,
  71                                         (sha256_block_fn *)sha2_ce_transform);
  72         kernel_neon_end();
  73         return sha256_base_finish(desc, out);
  74 }
  75
  76 static int sha256_ce_final(struct shash_desc *desc, u8 *out)
  77 {
  78         struct sha256_ce_state *sctx = shash_desc_ctx(desc);
  79
  80         sctx->finalize = 0;
  81         kernel_neon_begin_partial(28);
  82         sha256_base_do_finalize(desc, (sha256_block_fn *)sha2_ce_transform);
  83         kernel_neon_end();
  84         return sha256_base_finish(desc, out);
  85 }
  86
  87 static struct shash_alg algs[] = { {
  88         .init                   = sha224_base_init,
  89         .update                 = sha256_ce_update,
  90         .final                  = sha256_ce_final,
  91         .finup                  = sha256_ce_finup,
  92         .descsize               = sizeof(struct sha256_ce_state),
  93         .digestsize             = SHA224_DIGEST_SIZE,
  94         .base                   = {
  95                 .cra_name               = "sha224",
  96                 .cra_driver_name        = "sha224-ce",
  97                 .cra_priority           = 200,
  98                 .cra_flags              = CRYPTO_ALG_TYPE_SHASH,
  99                 .cra_blocksize          = SHA256_BLOCK_SIZE,
 100                 .cra_module             = THIS_MODULE,
 101         }
 102 }, {
 103         .init                   = sha256_base_init,
 104         .update                 = sha256_ce_update,
 105         .final                  = sha256_ce_final,
 106         .finup                  = sha256_ce_finup,
 107         .descsize               = sizeof(struct sha256_ce_state),
 108         .digestsize             = SHA256_DIGEST_SIZE,
 109         .base                   = {
 110                 .cra_name               = "sha256",
 111                 .cra_driver_name        = "sha256-ce",
 112                 .cra_priority           = 200,
 113                 .cra_flags              = CRYPTO_ALG_TYPE_SHASH,
 114                 .cra_blocksize          = SHA256_BLOCK_SIZE,
 115                 .cra_module             = THIS_MODULE,
 116         }
 117 } };
 118
 119 static int __init sha2_ce_mod_init(void)
 120 {
 121         return crypto_register_shashes(algs, ARRAY_SIZE(algs));
 122 }
 123
 124 static void __exit sha2_ce_mod_fini(void)
 125 {
 126         crypto_unregister_shashes(algs, ARRAY_SIZE(algs));
 127 }
 128
 129 module_cpu_feature_match(SHA2, sha2_ce_mod_init);
 130 module_exit(sha2_ce_mod_fini);